951721 has 4 divisors (see below), whose sum is σ = 969732. Its totient is φ = 933712.

The previous prime is 951697. The next prime is 951749. The reversal of 951721 is 127159.

951721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 127159 = 101 ⋅1259.

It can be written as a sum of positive squares in 2 ways, for example, as 876096 + 75625 = 936^2 + 275^2 .

It is a cyclic number.

It is not a de Polignac number, because 951721 - 2⁵ = 951689 is a prime.

It is a Duffinian number.

951721 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (951781) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8926 + ... + 9031.

It is an arithmetic number, because the mean of its divisors is an integer number (242433).

2⁹⁵¹⁷²¹ is an apocalyptic number.

It is an amenable number.

951721 is a deficient number, since it is larger than the sum of its proper divisors (18011).

951721 is a wasteful number, since it uses less digits than its factorization.

951721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18010.

The product of its digits is 630, while the sum is 25.

The square root of 951721 is about 975.5618893745. The cubic root of 951721 is about 98.3640837149.

The spelling of 951721 in words is "nine hundred fifty-one thousand, seven hundred twenty-one".